Society depends on accessible, responsive emergency medical care. Overcrowding and understaffing in Emergency Departments (ED) are serious issues and may adversely affect the health and safety of individuals in need of timely care. Despite emergency departments' critical "front-line" role, little is known about optimal physician and nurse staffing of Emergency Departments and their effects on patients' care and health outcomes for common urgent conditions. We propose to assess the relationship of Emergency Department physician and nurse staffing on time to treatment and patients' health outcomes for 3 delay sensitive conditions: appendicitis, ectopic pregnancy and intestinal obstruction. We will build on an ongoing AHRQ-funded project, "Assessing the Variability in Time to Treatment in Surgery." That study is collecting detailed information about symptom onset time, exam times, times of diagnosis and treatment, clinical characteristics and the course of care for patients with appendicitis, ectopic pregnancy and intestinal obstruction (N=409). In the proposed study, we will obtain data on emergency department physician and nurse staffing, patient census, and patients' level of nursing acuity from the emergency department's computer tracking software and other hospital data systems. The specific aims of this study are: 1. To explore and quantify the relationship between ED staffing and patient risk of adverse health outcomes. 2. To explore and quantify the relationship between ED staffing and different components of time to treatment. 3. To explore the relationship between the level of acuity of illness in the ED and different components of time to treatment. We will use multivariate analysis to examine the relationship of key ED physician and nurse staffing with time between patients' arrival to the ED and: 1) first emergency department examination; 2) diagnosis; 3) treatment; and with 4) rates of rupture for patients seen in the emergency department with the 3 delay sensitive conditions. These analyses will provide important information about the association of key emergency department staffing on patients' receipt of timely care and the health consequences of our current emergency delivery system.